(ii) GSK-HGS1006-C1057 (BLISS-52): A Phase 3, Multi-Center, Randomized, Double-Blind, Placebo-Controlled, 52-Wk Study to Evaluate the Efficacy and Safety of Belimumab (HGS1006, LymphoStat-B™), a Fully Human Monoclonal Anti-BLyS Antibody, in Subjects With Systemic Lupus Erythematosus (SLE)